When Professor Plum killed Dr Black, in the library, with the candlestick it was for no other reason than murder is a disease. Murder is infectious and the contagion of violence is everywhere.
Violence begets violence.Violence within nations and cultures. It occurs within families and between partners. It increases the risk of violence directed at children and increases the risk of the children behaving violently themselves. Violence within a community perpetuates and spreads. Children catch it from their parents, and parents can catch it from their children. Violence is highly contagious in all respects it seems.
It was a 2012 essay by L. Rowell Huesmann that sparked off a study, appearing in Justice Quarterly. A study with a simple premise and question; if homicide is infectious, it should diffuse through communities, infecting those susceptible, and that diffusion should be detectable. Much in the same way we can track the flu from year to year, we can track the spread of murder as an epidemic. It offers an interesting way of looking at murder and homicide.
Welcome to Newark, New Jersey. A city that houses roughly 277,000 people has a homicide and murder rate over three times greater than that of anywhere else in the US. There were 104 murders and 504 shooting victims in 2006 alone. Firearms were used in 71% of the 380 reported murders in 2011. Suffice it to say, Newark is not a safe place.
The study took a look at how murders and homicides moved and behaved over a 26-year period (1982 to 2008) across the city. Firearms and gangs were the infectious agents; spreading from within the centre of the city and spreading south-westerly over the course of nearly three decades.
Their main argument is that the way murders move across a community is not random. The elements required for disease to propagate itself may be relevant and can be applied to the movement of homicide. And if this is so, then it can be predicted and controlled.
If you take a look at a map of Newark it is hard to see a pattern. Homicides occurred in all parts of the city. Almost the entire city appears to be a hot spot for murder. But analysis over the decades suggest that there was expansion of overall homicides between 1982 and 2008 with a dip in 1997 and a sharp rise in 2000. And highlighted an area of the city (North and East) that seemed largely immune to the spread of homicide. Indeed, murder was on the move.
The criminal justice system seeks to prevent murder, but only after the fact — by deterring those that do it with the penalty that awaits them after the fact (jail and criminal prosecution). Indeed, police forces already have an eye out for certain hotspots within a location. Areas where violence is known to spark and ignite at any given moment. What they don’t know is where it will go next. The authors of the study model homicide as an infectious disease as simply a way to offer instructive understanding of how homicide works. The most telling application of this non-literal model is the fact that for homicide to spread as a disease, a population susceptible to transmission must be present. Just like every other infectious agent, except this time poverty and social inequality replace a population with no herd immunity.
Image — source
Zeoli, A., Pizarro, J., Grady, S., & Melde, C. (2012). Homicide as Infectious Disease: Using Public Health Methods to Investigate the Diffusion of Homicide Justice Quarterly, 1-24 DOI: 10.1080/07418825.2012.732100